On Christmas Eve (!) our washing machine packed up with a loud bang!
The fuse had blown. Against my better judgement my wife persuaded me
to simply replace the fuse and I was surprised when it appeared to do
the trick. However, not for long! The fuse then blew with another
loud bang.

I am wondering if this behaviour is likely to be the motor having
burned out or simply that the brushes need renewing. I've removed the
motor and the brushes. There is clear evidence of electrical burning
and black dust, but both brushes are intact, although I notice that one
is a few millimetres shorter than the other.

To me the logical next step is to risk replacing the brushes and if
that does not work decide on whether to try to test the motor.
Anyone have any suggestions or advice?

Thanks.

wrote in message
.com...
On Christmas Eve (!) our washing machine packed up with a loud bang!
The fuse had blown. Against my better judgement my wife persuaded me
to simply replace the fuse and I was surprised when it appeared to do
the trick. However, not for long! The fuse then blew with another
loud bang.

I am wondering if this behaviour is likely to be the motor having
burned out or simply that the brushes need renewing. I've removed the
motor and the brushes. There is clear evidence of electrical burning
and black dust, but both brushes are intact, although I notice that one
is a few millimetres shorter than the other.

To me the logical next step is to risk replacing the brushes and if
that does not work decide on whether to try to test the motor.
Anyone have any suggestions or advice?

Thanks.

I can't think of a situation where defective brushes would lead to a fuse
blowing. The motors are series wound and so brushes not making contact, will
reduce supply current rahter than blow a fuse.

It could be that the armature has developed a short on some sections and if
the motor comes to rest with these sections in contact with the brushes, the
fuse might blow on re-starting.
Motor testing is not trivial unless you have some reasonable specialist
equipment such as a variac. Do not be tempted to connect diectly to the
mains supply. The unloaded speed of these motors may destroy the windings.

I assume that when you replaced the fuse, that the motor did run for a
while, or did it blow as soon as the the motor first turned after filling?

if the former, I would think the motor is shot. If it were the controller at
fault, I would expect the fuse to blow instantly.

Good luck

Bob

On 27 Dec 2004 07:18:32 -0800, wrote:

On Christmas Eve (!) our washing machine packed up with a loud bang!
The fuse had blown. Against my better judgement my wife persuaded me
to simply replace the fuse and I was surprised when it appeared to do
the trick. However, not for long! The fuse then blew with another
loud bang.

I am wondering if this behaviour is likely to be the motor having
burned out or simply that the brushes need renewing. I've removed the
motor and the brushes. There is clear evidence of electrical burning
and black dust, but both brushes are intact, although I notice that one
is a few millimetres shorter than the other.

To me the logical next step is to risk replacing the brushes and if
that does not work decide on whether to try to test the motor.
Anyone have any suggestions or advice?

Thanks.

The brushes are a fiver and take half an hour to replace. Worth a try
before calling the repair man?

Although I have never had blown fuses from brushes. Smells, firework
displays and stuttering spins, but not fuses.

the motor did run again after replacing the fuse. in fact the washing
machine ran for in excess of 30 minutes before the second blow.

my wife says there might have been stuttering spins, but is not sure!
I wondered that if the motor stopped turning (because of a faulty
brush), then maybe the current through that particular winding would
increase enough to blow the fuse. If there were no movement there
wouldn't be any back-voltage. Maybe I'm just wishful thinking! I'll
see what others say but will probably change the brushes as a first
shot at a solution. Thanks.

On 27 Dec 2004 08:18:45 -0800, wrote:

my wife says there might have been stuttering spins, but is not sure!
I wondered that if the motor stopped turning (because of a faulty
brush), then maybe the current through that particular winding would
increase enough to blow the fuse. If there were no movement there
wouldn't be any back-voltage. Maybe I'm just wishful thinking! I'll
see what others say but will probably change the brushes as a first
shot at a solution. Thanks.

You are correct, motors like these are very crude and when they stop
with power on the brushes, a short circuit is very likely across the
segments.

If you do the brushes, be very gentle if you have to bend the metal
clips to get the old out and new in. They break very easily and
fabricating a replacement can be very boring.

In message . com,
writes
my wife says there might have been stuttering spins, but is not sure!
I wondered that if the motor stopped turning (because of a faulty
brush), then maybe the current through that particular winding would
increase enough to blow the fuse. If there were no movement there
wouldn't be any back-voltage. Maybe I'm just wishful thinking! I'll
see what others say but will probably change the brushes as a first
shot at a solution. Thanks.

Has a wire come loose which has chafed and is causing an intermittent
shout ?

--
geoff

wrote in message
oups.com...
On Christmas Eve (!) our washing machine packed up with a loud bang!
The fuse had blown. Against my better judgement my wife persuaded me
to simply replace the fuse and I was surprised when it appeared to do
the trick. However, not for long! The fuse then blew with another
loud bang.

I am wondering if this behaviour is likely to be the motor having
burned out or simply that the brushes need renewing. I've removed the
motor and the brushes. There is clear evidence of electrical burning
and black dust, but both brushes are intact, although I notice that one
is a few millimetres shorter than the other.

To me the logical next step is to risk replacing the brushes and if
that does not work decide on whether to try to test the motor.
Anyone have any suggestions or advice?

Thanks.


The build up of carbon from the brushes can cause arcing to the casing of
the motor, so if the area around the brushes is heavily coated with carbon
powder, then this can cause enough of an electrical arc to blow the fuse in
the plug.

You may be able to clean the motor enough, and extend the springs on the
brushes enough, to allow the machine to run for a little while longer until
you get to the shops for new carbons. A lot, if not all now, motors in the
likes of washing machines have carbon brushes already set in holders that
just slip into the motor casing. To replace them is as simple as removing
one wire spade connector and pressing a moulded clip on the holder to remove
it from the motor casing. Slide the new holder in to place and connect the
wire again.

Remember to clean all the old carbon dust from the motor with a vacuum
cleaner and a small paint brush. If the armature in the motor, the bit that
actually spins, is showing signs of burning, then gently turn it and place a
fine grade sand paper on the part the brushes sit on to clean them back to
the bare metal. They should be quite shiny and clean to make the motor run
properly again.

Good luck with it.

It was somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember raden saying
something like:

Has a wire come loose which has chafed and is causing an intermittent
shout ?

It'S pERfeCTly pOSSible, I WOUld thInk.
--

Dave

In message , Grimly
Curmudgeon writes
It was somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember raden saying
something like:

Has a wire come loose which has chafed and is causing an intermittent
shout ?

It'S pERfeCTly pOSSible, I WOUld thInk.

There's nothing worse than a nasty bit of chafing

--
geoff

"raden" wrote in message
...
In message , Grimly
Curmudgeon writes
It was somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember raden saying
something like:

Has a wire come loose which has chafed and is causing an intermittent
shout ?

It'S pERfeCTly pOSSible, I WOUld thInk.

There's nothing worse than a nasty bit of chafing

geoff


But the prescription cream and loose underwear can help a lot. :-)

The brushes are a fiver and take half an hour to replace. Worth a try
before calling the repair man?

1/2 hour !!!!!!!


Peter

On Tue, 28 Dec 2004 13:23:18 +0000 (UTC), "Peter"
strung together this:



The brushes are a fiver and take half an hour to replace. Worth a try
before calling the repair man?

1/2 hour !!!!!!!

That's including the coffee break half way through and a test cycle.
--

SJW
Please reply to group or use 'usenet' in email subject

On Tue, 28 Dec 2004 14:09:36 UTC, Lurch
wrote:

On Tue, 28 Dec 2004 13:23:18 +0000 (UTC), "Peter"
strung together this:



The brushes are a fiver and take half an hour to replace. Worth a try
before calling the repair man?

1/2 hour !!!!!!!

That's including the coffee break half way through and a test cycle.

And unstacking the tumble dryer.
--
Bob Eager
begin a new life...dump Windows!

wrote:
in fact the washing machine ran for in excess of 30 minutes before
the second blow.

Would it have reached the stage in the cycle where the pump is
activated? My Hotpoint suffered nasty chafing of the wires supplying
the pump power, resulting in a short and fuse blowing at the end of the
wash cycle.

BigWallop wrote:
wrote in message
oups.com...
On Christmas Eve (!) our washing machine packed up with a loud
bang!
The fuse had blown. Against my better judgement my wife persuaded
me
to simply replace the fuse and I was surprised when it appeared to
do
the trick. However, not for long! The fuse then blew with another
loud bang.

I am wondering if this behaviour is likely to be the motor having
burned out or simply that the brushes need renewing. I've removed
the
motor and the brushes. There is clear evidence of electrical
burning
and black dust, but both brushes are intact, although I notice that
one
is a few millimetres shorter than the other.

To me the logical next step is to risk replacing the brushes and if
that does not work decide on whether to try to test the motor.
Anyone have any suggestions or advice?

Thanks.


The build up of carbon from the brushes can cause arcing to the
casing of
the motor, so if the area around the brushes is heavily coated with
carbon
powder, then this can cause enough of an electrical arc to blow the
fuse in
the plug.

You may be able to clean the motor enough, and extend the springs on
the
brushes enough, to allow the machine to run for a little while longer
until
you get to the shops for new carbons. A lot, if not all now, motors
in the
likes of washing machines have carbon brushes already set in holders
that
just slip into the motor casing. To replace them is as simple as
removing
one wire spade connector and pressing a moulded clip on the holder to
remove
it from the motor casing. Slide the new holder in to place and
connect the
wire again.

Remember to clean all the old carbon dust from the motor with a
vacuum
cleaner and a small paint brush. If the armature in the motor, the
bit that
actually spins, is showing signs of burning, then gently turn it and
place a
fine grade sand paper on the part the brushes sit on to clean them
back to
the bare metal. They should be quite shiny and clean to make the
motor run
properly again.

Good luck with it.


Replacing the brushes didn't work, but replacing the motor did! Thanks
to you guys for your helpful advice and comments.